Analysis of Optical Fiber Application Technology Based on Cabling Technology

Analysis of Optical Fiber Application Technology Based on Cabling Technology

1 key points of data center optical fiber design

(1) minimum allowable bending radius: In which case the installation of optical fiber is much easier than that of coaxial and UTP copper cables. The most important factor in cable installation is to keep the minimum bending radius of the cable. When the optical cable is smaller than the minimum allowable bending radius, the loss may increase or the fiber is broken. If the child or outer sheath is not damaged, the attenuation value of the Bent Optical Cable is restored to the normal value when the stress is released. When the optical cable manufacturer leaves the factory, the minimum allowable bending radius is specified when the optical cable is in short-term external force and long-term maintenance. Generally, the bending radius allowed when the optical cable is not stressed is 10 times that of the outer diameter of the cable. When an external force exists, the typical minimum allowable bending radius is 15 times that of the outer diameter.

(2) Maximum Tension evaluation: during the installation of the optical cable, the tension value of the optical cable cannot exceed the maximum allowable tension. This value depends on the definition of the optical cable manufacturer. When the optical cable is laid using a mechanical traction device, the tension value of the optical cable shall not be too large. During manual laying, you do not need to monitor the device. For the laying of Optical Cables with roundabout routes, you can use the reverse release and winding mode or the wire rod and disk axis technology. For the installation of indoor optical cables, use a junction box for three right turns to facilitate cable pulling. In addition to the self-weight in the vertical section, the optical cable shall not be subjected to any residual tension after installation.

(3) maximum vertical height: All optical cables have a maximum allowable vertical height value, because of the dual effect of optical cable self-weight and external tension. This value indicates the maximum distance supported by the optical cable when no intermediate point is installed in the vertical space.

Precautions for installation of vertical spatial optical cables:

The vertical trunk cable must not be covered by other laid cables;

At the point of contact of the fixed cable, the minimum allowable bending radius of the optical cable must be ensured.

The correct installation method is to use nylon mesh handles for laying, so that the optical cable's self-weight is borne by the handle of the entire cable covered, and the handle is set at the interval of the entire optical cable, this type of segment setting is used to prevent damage to the optical fiber due to accidental sliding of the optical fiber.

(4) routing and Space: an important part of the cabling network design is to select appropriate cable routes (including but not limited to factors such as cable slots, cable trays, and vertical channels) and ensure a certain amount of end space (including but not limited to factors such as main/intermediate/vertical cross interconnection, device area wiring, etc ). The following standards can be referenced: TIA942 of data center telecommunications infrastructure standards, TIA/EIA569 of commercial construction telecommunications routing and space standards, and the telecommunications wiring method manual developed by BICSI.

(5) optical cable protection: for cables that may be attached to the same pipe or cable trough in the future, we recommend that you use sub-tubes to pre-allocate available cabling space. If this isolation is not available, the attached optical cable may be wound during stretching and the service may be interrupted. Use as straight as possible to protect the cables, so as to prevent cable freezing and sprains during installation.

When the optical fiber cables are laid in pipelines, pallets, and ensure the connection security between cables, you need to consider the shift of the existing optical fiber cables. Optical Cables running online can only be moved without affecting the transmission service. Pay special attention to the parts that are physically damaged in the cable trough.

(6) pipeline utilization rate: It is recommended that the channel or trough be used to pull the laid optical cable. The cross section filling rate of the pipe or trough is less than 65%. For example, the diameter of a single optical cable in a pipe with an diameter of 25. 4mm is 20.3mm. In a large cable trough, as long as the tension load of each optical fiber cable and the cross section filling rate of the pipeline are allowed, multiple and multiple optical cables can be laid at one time. It is recommended that the filling rate of two cables be 30%, and that of three or more cables be 40%.

(7) Fill Rate of optical fiber cables: The fill rate of optical fiber cables provides a budget for the future number of optical fiber cables as demand increases. Multi-core optical fiber cables have a higher laying density than single-core optical fiber cables with the same number of optical fiber cables. Therefore, when using multi-core optical fiber cables, some cores are reserved until end-to-end connection is required. The cost of such front-end applications is very low, especially for those optical cables that are difficult to lay.

(8) Building Fire Prevention specifications: whether inside or outside a building, telecommunication cabling facilities must comply with the Building Fire Prevention specifications. In view of the limited space, we will introduce this part in a special article.

2 key points of data center optical fiber construction

2.1 installation points of pre-connection trunk cable

The conventional indoor optical fiber cables are not described here. For data centers, it is best to have wireless communication or other two-way routing communication between the two optical fiber connection endpoints for emergency needs. Once there is a twist or other problem during the stretching process, smooth real-time communication can terminate the wrong construction in time to avoid further damage to the optical fiber cable and Optical Fiber Connector. This is crucial.

(1) The traction handle installed on the pre-connected optical fiber cable to the data center has protected the optical fiber cable itself, the optical fiber connectors at both ends and the corresponding sub-units. Therefore, it is not necessary to cut the traction handle and its internal optical cable like a conventional indoor optical cable, but to follow the specific steps described in this article to remove the traction handle from the optical fiber connector and its sub-units.

(2) do not use any lubricant when the traction handle is installed on the data center optical cable.

(3) optical cables are sensitive to excess pressure, bending, and pressure. Before construction, please refer to the optical cable specifications. Make sure that the bending radius of the optical cable is greater than the minimum allowable value to prevent the cable from being squeezed or twisted. Once the above conditions affect the Optical Fiber Transmission Performance, you must re-deploy the optical fiber.

(4) Only manual pull of the traction handle is allowed, and any mechanical traction device is prohibited from acting on the handle.

(5) Note: The maximum tensile strength of the pre-connected optical cable in the data center is 100 lbs. The minimum allowable bending radius of the traction handle is 45.72com. For other dimensions of the optical cable and traction handle, refer to the product specifications to select the appropriate cable slot.

2.2 laying protection for pre-connection trunk cable

The premise of the following steps is that the cable cabling routes are arranged along the cable trough, and the routes contain necessary accessories to ensure the bending radius of the traction handle.

Remove the foam plastic pallets protecting optical cables in the freight box if necessary;

Route the optical cable with one end of the traction handle from the disc;

Fasten the rope at the casing ring at the front end of the optical cable traction handle to be laid out;

The minimum allowable bending radius and maximum tensile force are arranged according to the installer's operation procedure.

Demolition of pre-connection Optical Cable traction handles in data centers:

(1) Remove the rope and dirt from the casing. Note: The optical cable carries a large amount of dirt in harsh environments such as dust, overheating, or liquid.

(2) uncover the cover and open the zipper canvas casing.

(3) Separate the bellows and the splitter in the casing to expose the branch of the optical fiber connector.

(4) split the branch plug into two halves by the protruding part of the shell splitter.

(5) pre-connection trunk cable for 96-core 144-core: disconnects a set of nylon mesh covers closest to the branch plug. Uncover the tape, remove the network covers, and expose a group of branch packages. The radius of the expanded branch must be greater than the minimum allowable radius. Repeat the preceding steps until several network sets are removed.

(6) Ensure that the branch plug of the trunk cable is mounted to the distribution frame of the data center using a snap-in clamp.

2.3 optical cable connection component Operation Method

(1) dual-core jumper and fan-out Jumper: Optical jumper is sensitive to excess tension, bending, and pressure. Before construction, you must refer to the optical cable specifications. If the above conditions occur, you must re-adjust the deployed optical cable.

(2) cleaning and Protection of optical fiber connectors

Clean the connector end face mounted on the adapter with a dedicated LC cleaning tool (P/NCLEANER-PORT-LC. For the MTP connector, the same is true (P/N2104466-01 ). In addition, dedicated tools (CLEANER-UNIV-CASS) can be used to clean commonly used types of fiber optic connectors. Whether the connector is single-core or multi-core. Do not remove the dust cap that comes with the factory before using the optical fiber connector.